London's long lost Roman amphitheatre, said to be roughly the size of the old Wembley stadium, turned up under the Guildhall in February 1988.
The amphitheatre at Pompeii was usually the venue for bloodier spectacles than those you could catch at its semi-circular rival in midtown. Yet in AD 59 it was the setting for what modern tabloid journalists insistently refer to as a tragedy. (Along the lines of "Heisel tragedy".)
It's an old model from 80 BC, pre-dating Rome's first amphitheatre by about a century. It lacks the later Colliseum's under-stage gizmos and sports just two main entrances at either end of the oblong arena which seated up to 20,000. Visiting Nucerians had a habit of scribbling graffiti on the walls advertising the comparatively modern facilities they enjoyed back home.
Tacitus explains how the clash between locals and the fans from Nuceria got going that day. "With the unruly spirit of townsfolk, they began with abusive language of each other; then they took up stones and at last weapons, the advantage resting with the populace of Pompeii, where the show was being exhibited." The lack of exits made the fracas especially lethal for the hard-pressed away supporters, many of whom tumbled to their deaths from the top tier.
After a party of aggrieved Nucerians travelled to Rome to complain to Nero about the incident gladiatorial games were banned in Pompeii for ten years. The amphitheatre was still used for less deadly activities and the magistrates rented out the spaces under the arches to working girls.
On a separate note, one of the more striking facts I have picked up since our visit to Pompeii was that you were much more likely to die of malaria if you had one of these attractive rectangular pools in your atrium!